Stainless Steel Carbon Steel Blind Flanges Manufacturer

Stainless Steel Carbon Steel Blind Flanges Manufacturer Suppliers Dealer Exporter in India

Blind Flanges are manufactured with top quality materials in different sizes according to the customers requirements. Nitech Stainless is the leading Blind Flanges Supplier, Manufacturer, dealer & Exporter in India. Nitech Stainless is known worldwide for its extensive high quality range of Buttwelded Pipe Fittings. At Nitech Stainless we have our own research centre to help gather the required knowledge about the latest technologies & keep on increasing the quality of the product with each new research in our research centre.

Stainless Steel Carbon Steel Blind Flanges Supplier, Dealer, Manufacturer & Exporter in India

Nitech Stainless Inc is leading manufacturer of Blind Flanges. Blind Flanges are available from 1/2″NB to 25″NB & in different types & wall thicknesses. Nitech Stainless Manufacturers & suppliers of high-quality Blind Flanges. Also available in special sizes & materials as per the customers requirements.

About Blind Flanges

A flange is an external or internal ridge, or rim, for strength, as the flange of an iron beam such as an I-beam or a T-beam ; or for attachment to another object, as the flange on the end of a pipe, steam cylinder, etc., or on the lens mount of a camera or for a flange of a rail car or tram wheel . Thus flanged wheels are wheels with a flange on one side to keep the wheels from running off the rails . The term “flange” is also used for a kind of tool used to form Blind Flanges. Pipes with Blind Flanges can be assembled & disassembled easily.

Blind Flanges Standard

ASA, ASME, ANSI (USA), PN, DIN (European), BS10 (British/Australian), & JIS, KS (Japanese/Korean).

Materials used to make Blind Flanges

Blind Flanges are available in many different materials. Such as – Stainless Steel Blind Flanges, Alloy Steel Blind Flanges, Carbon Steel Blind Flanges, Aluminium Blind Flanges, Duplex Steel Blind Flanges, Hastelloy Blind Flanges, Incoloy Blind Flanges, Inconel Blind Flanges, Monel Blind Flanges, Nickel Alloy Blind Flanges, Nitronic Alloy Blind Flanges, Titanium Blind Flanges,

Types of Flanges Manufacturers Suppliers Dealers in Mumbai India

Slip On Flanges, Blind Flanges , Weld Neck Flanges, Threaded Flanges, Long Weld Neck Flanges, Socket Weld Flanges, Studding Outlet Flanges, Lap Joint FLanges, Companion Flanges are some of the types of Flanges that we offer at Nitech Stainless Inc.

Nitech Stainless is leading Manufacturer of flanges, buttwelded pipe fittings & Pipes & Tubes in India

Nitech Stainless Inc is manufacturers, dealers, suppliers of Blind Flanges in India. Nitech Stainless Inc is the leading supplier of other products such as Pipes and Tubes, Buttwelded Pipe Fittings. Nitech Stainless Inc has a wide range of products available in different materials & grades. We also offer products as per customers requirements & specifications.

Nitech Stainless Inc is one of the largest manufacturers & suppliers of Blind Flanges in India

Nitech Stainless Inc has created a name in the Indian market as the leading manufacturer & supplier of Blind Flanges in India. Nitech Stainless Inc has its manufacturing plants at different cities of India.

Our steel flanges contain prime quality materials. factory-made from quality steel meeting ASTM &/or AISI standards as a result of higher the standard, higher is that the toughness of the ASTM | ASME | ANSI flanges. prime quality of steel content makes an ASTM | ASME | ANSI flanges harder & will increase its hardness. Nitech Stainless Inc is specialized in manufacturer & suppliers of steel flanges in India. Nitech Stainless Inc may be a certified manufacturer & suppliers in India. Nitech Stainless Inc is wide common in India for its prime quality steel flanges product.

Nitech Stainless Inc manufacturers & provides solely quality tested & difficult ASTM | ASME | ANSI flanges. ASTM | ASME | ANSI flanges at Nitech Stainless Inc bear several toughness & hardness check before provision it to our purchasers. we’ve over 99% happy purchasers.

Our purchaser’s satisfaction depends on a variety of things like quality, Toughness, Hardness, Delivery Time & our Services for ASTM | ASME | ANSI flanges. Nitech Stainless Inc may be a Indian suppliers of steel flanges in INDIA. Nitechtech Stainless is also a leading supplier & dealer of other flanges such as Stainless Steel Flanges, Alloy Flanges in INDIA. Nitech Stainless also is a market leader of other products such as ASTM | ASME | ANSI Flange, Stainless Steel pipe & tubes, buttweld pipe fitting, Weld Neck Flanges, Slip-On Flanges & many more other products in INDIA.

ANSI Flanges Class 150, ANSI Flanges Class 300, ANSI Flanges Class 400, ANSI Flanges Class 600, ANSI Flanges Class 900, ANSI Flanges Class 1500, ANSI Flanges Class 2500, ASTM Flanges Class 150, ASTM Flanges Class 300, ASTM Flanges Class 400, ASTM Flanges Class 600, ASTM Flanges Class 900, ASTM Flanges Class 1500, ASTM Flanges Class 2500, ASME Flanges Class 150, ASME Flanges Class 300, ASME Flanges Class 400, ASME Flanges Class 600, ASME Flanges Class 900, ASME Flanges Class 1500, ASME Flanges Class 2500,

Stainless Steel Carbon Steel Studding Outlet Flanges

Studding Outlet Flanges are manufactured with top quality materials in different sizes according to the customers requirements. Nitech Stainless is the leading Studding Outlet Flanges Supplier, Manufacturer, dealer & Exporter in India. Nitech Stainless is known worldwide for its extensive high quality range of Buttwelded Pipe Fittings. At Nitech Stainless we have our own research centre to help gather the required knowledge about the latest technologies & keep on increasing the quality of the product with each new research in our research centre.

Stainless Steel Carbon Steel Studding Outlet Flanges Pipe Fitting Supplier, Dealer, Manufacturer & Exporter in India

Nitech Stainless Inc is leading manufacturer of Studding Outlet Flanges. Studding Outlet Flanges are available from 1/2″NB to 25″NB & in different types & wall thicknesses. Also available in special sizes & materials as per the customers requirements.

About Studding Outlet Flanges

A flange is an external or internal ridge, or rim, for strength, as the flange of an iron beam such as an I-beam or a T-beam ; or for attachment to another object, as the flange on the end of a pipe, steam cylinder, etc., or on the lens mount of a camera or for a flange of a rail car or tram wheel . Thus flanged wheels are wheels with a flange on one side to keep the wheels from running off the rails . The term “flange” is also used for a kind of tool used to form Studding Outlet Flanges. Pipes with Studding Outlet Flanges can be assembled & disassembled easily.

Studding Outlet Flanges Standard

ASA, ASME, ANSI (USA), PN, DIN (European), BS10 (British/Australian), & JIS, KS (Japanese/Korean).

Materials used to make Studding Outlet Flanges

Types of Flanges Manufacturers Suppliers Dealers in Mumbai India

Nitech Stainless is leading Manufacturer of flanges, buttwelded pipe fittings & Pipes & Tubes in India

Nitech Stainless Inc is manufacturers, dealers, suppliers of Studding Outlet Flanges in India. Nitech Stainless Inc is the leading supplier of other products such as Pipes and Tubes, Buttwelded Pipe Fittings. Nitech Stainless Inc has a wide range of products available in different materials & grades. We also offer products as per customers requirements & specifications.

Nitech Stainless Inc is one of the largest manufacturers & suppliers of Studding Outlet Flanges in India

Nitech Stainless Inc has created a name in the Indian market as the leading manufacturer & supplier of Studding Outlet Flanges in India. Nitech Stainless Inc has its manufacturing plants at different cities of India.

Our steel flanges contain prime quality materials. factory-made from quality steel meeting ASTM and/or AISI standards as a result of higher the standard, higher is that the toughness of the ASTM | ASME | ANSI flanges. prime quality of steel content makes an ASTM | ASME | ANSI flanges harder & will increase its hardness. Nitech Stainless Inc is specialized in manufacturer & suppliers of steel flanges in India. Nitech Stainless Inc may be a certified manufacturer & suppliers in India. Nitech Stainless Inc is wide common in India for its prime quality steel flanges product.

Various Factors Used to Identify Stainless Steel Flange

Whether a Stainless Steel Flange will function properly all goes back to whether the flange was the right one for the job in the first place. A flange must fit in pipe joints just right in order for it to perform properly. A small error in choosing a flange can affect an application resulting in a costly mistake. These factors are all involved in choosing the right flange for the right application to maximize its functionality.

· Types

It’s pretty easy to identify the type of flange by how it looks. First, identify the tops by determining whether a flange has a flat face, threaded bore, lap joint, weld neck, socket weld, or tongue and groove. Next is identifying the bottoms by determining whether it has a flat face, which is completely flat or a raised face which is a slightly raised section on the face of the flange.

· Size

The size of a flange is comprised of factors that include the standard used (ANSI/DIN/JIS), pressure class needed, and the actual measurements of an ASTM Flange Class 300. Factors include the outer diameter, inner diameter, number of bolt holes, bolt hole diameter, and the bolt circle.

· Thickness

Thickness play a vital role in identifying a flange by how high of a pressure it can withstand because thicker flanges can withstand higher pressures in an application.

· Bolt Holes

This component helps determine the size of a flange and pressure class. 3 factors that need to be considered are the amount of bolt holes, pitch circle diameter, and actual size of the bolt holes on a flange. The thicker the bolt the stronger the bolt is, resulting in a higher pressure that the flange can withstand.

· Standards

There are a number of standards that can be selected from. The selection will most likely be based upon the application and standards of the other components that this flange will be connected to. (i.e. valves) 3 main standards used are: ANSI – American National Standards Institute, DIN – Detaches Institute fur Norming / European, and JIS – Japanese International Standard. Click here to know more about Stainless steel flanges manufacturer in India.

· Pressure Class

Pressure class represents the nominal amount of pressure that the product can support or operate under safely. Each standard has multiple pressure classes available ranging from low pressure tolerance to high pressure tolerance. The pressure class of products working together should be the same matching the pressure class of the pipes and valves in the system that it is connected to.

· Materials

It is important to choose the right material for a flange and understand the elements that it will face in an application the piping system is being used. (corrosion, pressure, moisture, temperature) Common materials include steel, stainless steel, carbon steel, and copper nickel.

Various Advantages of Using 304 Stainless Steel Flanges

Stainless Steel is known to be the most versatile grade from tubing, to cutlery, to appliances, stainless steel is used in various different applications because it has many beneficial properties.

Stainless steel’s chromium & nickel component–which comprises a minimum of 18% Cr & 8% Ni of the total material–gives it this beneficial property. When exposed to oxygen, the chromium forms a thin, imperceptible passivation layer on the surface of the steel. It’s invulnerable to water & air, & it also reforms quickly if scratched, making stainless steel pipe, fittings, & flanges excellent choices

Here are a handful of those properties that make it an excellent choice for flanges.

Stain & Corrosion Resistant – Stainless Steel 304 Flanges are exceptional in a wide range of atmospheric environments & many corrosive media. It is resilient to pitting & crevice corrosion in warm chloride environments, & resistant to stress corrosion cracking below 60° C (approximate). SS 304 Flanges are resistant to potable water up to approximately 200 mg/L chlorides at ambient temperatures

Value – When you use 304 stainless steel flanges, you are buying a long-lasting product that will last your project for decades. It is a consistent material that is easy to maintain & install. Stainless steel is low-maintenance, & due to its corrosion-resistant properties, it is unlikely they will need to be replaced for decades.

Strength & Versatility – Different materials such as nickel, molybdenum, or nitrogen can be added to stainless steel to enhance its corrosion-resistant properties. ASTM A182 Flanges can handle extreme temperatures & has higher strength at elevated temperatures so is often used for structural & pressure-containing applications at temperatures above 500 degrees C up to about 800 degrees C (approximate).

Appearance –Stainless Steel Flange is an excellent choice for commercial establishments as the material has a naturally shiny & elegant look.

Environment-friendly – Stainless steel is not a petroleum product. In fact, it doesn’t need to be coated or lined with any materials at all, unlike other materials. When you need to replace or dispose of stainless steel flanges, it is 100 percent recyclable, reducing the environmental impact. As much as 50 percent of all new stainless steel that is produced in the United States is made from recycled scrap metal.

Applications- Thanks to its versatility & durability, stainless steel is known for being a “miracle metal” that is used for countless commercial & industrial applications like Food processing equipment, particularly in beer brewing, milk processing & winemaking, kitchen benches, sinks, troughs, equipment & appliances, heat exchangers, etc.

Slip On Flanges, all you need to know about them

stainless steel carbon steel slip on flanges

Slip on Flange is actually a hoop that’s placed over the pipe end, with the flange face extending from the top of the pipe by enough distance to use a weld bead on the inside diameter.

The OD of the slip-on flange is additionally welded on the rear side of the flange. Slip-on flanges have a lower material cost than weld neck flange and are more easily aligned.

Slip-on flange can also be used joint flanges if B or Type C stub ends are used.

What is slip on Flanges used for?

Slip On flange features a hole with matching outside diameter of pipe from which pipe can pass. The flange is placed on pipe and fillet welded from both inside and out of doors. Slip On Flange is suitable for low and temperature applications. this sort of flange is out there in large sizes also to attach big-bore piping with tank nozzles. Normally, these flanges are of forged construction and are given the hub. Sometimes, these flanges are fabricated from plates and aren’t given the hub.

Slip-on Flange Pressure-Temperature category:

The Slip On Flange is assessed as per their pressure-temperature ratings that are selected as 150#, 300#, 400#, 600#, 900#, 1500# and 2500#. Massive diameter flanges that are 24” to 60” are accessible up to 900# category. Pressure-temperature ratings are the most allowable operating gauge pressures among the bar & the temperatures in degrees Celsius. Higher the rating, heavier the flange and will stand up to higher pressure and temperature. Once the temperature goes up, the pressure goes down, and also the alternative approach around.{Please note that totally different|completely different} material has different pressure ratings.

Material Used For manufacturing Slip On Flange:

Flanges are factory-made from,

Carbon steel

Low alloy steel

Stainless steel

Combination of Exotic materials (Stub) and alternative packing materials

The list of materials conversant in manufacture flanges is roofed in ASME B16.5 & B16.47.

ASME B16.5 – Slip on Pipe Flanges and Slip on Flanged Fittings NPS ½” to 24”

ASME B16.47 -Large Diameter Steel Slip on Flanges NPS 26” to 60”

Commonly used solid material grads for Manufacturing Slip-on Flanges are

Carbon Steel: — ASTM A105, ASTM A350 LF1/2, ASTM A181

Alloy Steel: — ASTM A182F1 /F2 /F5 /F7 /F9 /F11 /F12 /F22

Stainless Steel: — ASTM A182F6 /F304 /F304L /F316 /F316L/ F321/F347/F348

Slip-On Flange Inspection:

Following to be confirmed throughout associate inspection of a Slip-On flange,

Outer & Inner Diameter of body

Bolt Circle & Bolt hole Diameter

Hub Diameter & thickness of weld finish

The Length of the Hub

Straightness and alignment of the bolt hole

Permissible tolerances are given in B16.5 and B16.47 standards.

Slip On Flanges, all you need to know about them.

Slip on Flange is actually a hoop that’s placed over the pipe end, with the flange face extending from the top of the pipe by enough distance to use a weld bead on the inside diameter.
The OD of slip on flange is additionally welded on the rear side of the flange. Slip on flanges have a lower material cost than weld neck flange and are more easily aligned.
Slip on flange can also be used joint flanges if B or Type C stub ends are used.

What is slip on Flanges used for?
Slip-On flange features a hole with matching outside diameter of pipe from which pipe can pass. The flange is placed on pipe and fillet welded from both inside and out of doors. Slip-On Flange is suitable for low and temperature applications. this sort of flange is out there in large sizes also to attach big-bore piping with tank nozzles. Normally, these flanges are of forged construction and are given the hub. Sometimes, these flanges are fabricated from plates and aren’t given the hub.

Slip on Flange Pressure-Temperature category:
The Slip On Flange is assessed as per their pressure-temperature ratings that are selected as 150#, 300#, 400#, 600#, 900#, 1500# and 2500#. Massive diameter flanges that are 24” to 60” are accessible up to 900# category. Pressure-temperature ratings are the most allowable operating gauge pressures among the bar & the temperatures in degrees Celsius. Higher the rating, heavier the flange and will stand up to higher pressure and temperature. Once the temperature goes up, the pressure goes down, and also the alternative approach around.{Please note that totally different|completely different} material has different pressure ratings.

Material Used For manufacturing Slip On Flange:
Flanges are factory-made from,
Carbon steel
Low alloy steel
Stainless steel
Combination of Exotic materials (Stub) and alternative packing materials

The list of materials conversant in manufacture flanges is roofed in ASME B16.5 & B16.47.
ASME B16.5 – Slip on Pipe Flanges and Slip on Flanged Fittings NPS ½” to 24”
ASME B16.47 -Large Diameter Steel Slip on Flanges NPS 26” to 60”

Commonly used solid material grads for Manufacturing Slip on Flanges are
Carbon Steel: — ASTM A105, ASTM A350 LF1/2, ASTM A181
Alloy Steel: — ASTM A182F1 /F2 /F5 /F7 /F9 /F11 /F12 /F22
Stainless Steel: — ASTM A182F6 /F304 /F304L /F316 /F316L/ F321/F347/F348

Slip On Flange Inspection:
Following to be confirmed throughout associate inspection of a Slip On flange,
Outer & Inner Diameter of body
Bolt Circle & Bolt hole Diameter
Hub Diameter & thickness of weld finish
The Length of the Hub
Straightness and alignment of the bolt hole

Permissible tolerances are given in B16.5 and B16.47 standards.

Tips to Using A Pipe Flange For The Very First Time

A pipe flange is a mechanical product that serves the purpose of joining pipes together. It can be in the form of a welding neck where it’s welded to the flange collar or threaded where it’s screwed to the flange. Other approaches include the use of a lap joint to make connections using a stub end, or a socket weld or a slip on.

Here are 5 tips to use a flange for the first time:

1. Use Slip-on Flanges in Low-Pressure Services

Slip-on flanges are more chosen by users owing to them being low cost, taking less time to install, & their ease of use. They are used for non-critical low-pressure services like cooling water, fire water, & other non-challenging pipework owing to their strength being 1/3 lower than that of a weld neck flange. The pipe gets welded to the flange bore & hub. To check how proper the slip-on connection is, a simple visual examination, a magnetic particle, or a PT test are the approaches one can follow.

2. Use Socket Weld Flanges in High-Pressure Pipe Works

When doing high-pressure pipe works that are below 2 inch (DN50), socket weld flanges are more chosen. Good welding experience is dynamic to making this connection since a radiographic examination on the fillet weld is not easily executable. If, however, the connection is critical & visual examination alone won’t be enough, you can carry out liquid penetrant or magnetic particle tests to check the strength of the connection.

3. Use Lap Joint Flanges in High-Cost Material Pipelines

Lap joint Flanges work well for pipelines that are in high-cost materials such as nickel alloys & stainless steel as it greatly reduces the total cost or all the flanged connections that are needed. A lap joint connection is made by combining the stub end which has been welded onto the pipe & the lapped flange or backing flange. You can, for example, use a stainless steel stub end combined with a carbon steel lap joint flange to get a proper welded connection at a very low cost. Lap joint flanges usually have a raised face & are generally sealed with a flat ring gasket.

4. Connect Weld Neck Flanges to A Butt Weld Pipe for Better Performance

There is a tapered hub on the weld-neck flanges with an end that’s butt weld that can be linked to a butt weld pipe. You can test the quality of the weld using radiography, ultrasound or it can be done visually. The welded connection of a pipe & a weld neck flange features good fatigue as well as mechanical stress performance.

5. Ensure That A Skilled Professional Executes Pipe Flange Joints

Trained personnel should be the ones to perform flange joints to prevent any unsafe leakages from happening in the pipeline. As flanges are being used for the first time, an accurately trained engineer should be the one to execute the flanged joints.

Benefits of Using Stainless Steel 304 Flanges

Stainless Steel is known to be the most versatile grade from tubing, to cutlery, to appliances, stainless steel is used in various different applications because it has many beneficial properties.

Here are a handful of those properties that make it an excellent choice for flanges.

Stain & Corrosion Resistant – Stainless Steel 304 Flanges are exceptional in a wide range of atmospheric environments & many corrosive media. It is resilient to pitting & crevice corrosion in warm chloride environments, & resistant to stress corrosion cracking below 60° C (approximate). SS 304 Flanges are resistant to potable water up to approximately 200 mg/L chlorides at ambient temperatures

Value – When you use 304 stainless steel flanges, you are buying a long-lasting product that will last your project for decades. It is a consistent material that is easy to maintain & install. Stainless steel is low-maintenance, & due to its corrosion-resistant properties, it is unlikely they will need to be replaced for decades.

Strength & Versatility – Different materials such as nickel, molybdenum, or nitrogen can be added to stainless steel to enhance its corrosion-resistant properties. ASTM A182 Flanges can handle extreme temperatures & has higher strength at elevated temperatures so is often used for structural & pressure-containing applications at temperatures above 500 degrees C up to about 800 degrees C (approximate).

Appearance –Stainless Steel Flange is an excellent choice for commercial establishments as the material has a naturally shiny & elegant look.

Environment-friendly – Stainless steel is not a petroleum product. In fact, it doesn’t need to be coated or lined with any materials at all, unlike other materials. When you need to replace or dispose of stainless steel flanges, it is 100 percent recyclable, reducing the environmental impact. As much as 50 percent of all new stainless steel that is produced in the United States is made from recycled scrap metal.

Applications- Thanks to its versatility & durability, stainless steel is known for being a “miracle metal” that is used for countless commercial & industrial applications like Food processing equipment, particularly in beer brewing, milk processing & winemaking, kitchen benches, sinks, troughs, equipment & appliances, heat exchangers, etc.

To know more about stainless steel flanges, visit flanges manufacturer in India.

ANSI B16.5 Flange

Nitech Stainless is a trusted ANSI B16.5 Flange manufacturers in India. We have more years of experience in Exporting ANSI B16.5 Class 150 Flanges are stocked or available in the different range of sizes and materials which are used for different industries such as petrochemical, oil, gas, food, and allied industries. Our high-end technology has been designed to produce ANSI B16.5 Flange according to global Industrial Standards. Our ANSI B16.5 Flange is well checked in terms of quality before delivering it to our customers.

Standard Specification For ANSI B16 5 Flange

Dimensions: ANSI B16.5, ASME B16.5

Size: 1/2″ (15 NB) to 48″ (1200NB)

Class: class 150, class 300, class 600, class 900, class 1500, class 2500.

DIN: DIN2527, DIN2566, DIN2573, DIN2576, DIN2641, DIN2642, DIN2655, DIN2656, DIN2627, DIN2628, DIN2629, DIN 2631, DIN2632, DIN2633, DIN2634, DIN2635, DIN2636,DIN2637, DIN2638, DIN2673

BS: BS4504 , BS4504, BS1560, BS10

Flange Face Type: Flate Face (FF), Raised Face (RF), Ring Type Joint (RTJ)

About ANSI B16.5 Flange

ANSI B16.5 Pipe Flanges and Flange Fittings standard covers a number of product attributes, including pressure ratings, temperature ratings, materials, dimensions, tolerances, marking and testing. Resistant to bending, dishing and expansion, these flanges are strong and stable. Nitech Stainless Inc is one of the leading ANSI16.5 Flange manufacturers in India. ANSI B16.5 standard covers Pipe Flanges and Flanged Fittings for size NPS ½” to 24” for above NPS 26” to 60”.

ANSI B16.5 Flange Types

Products
ANSI B 16.5 Slip-On Flange	ANSI B16.5 Socket Weld Flange
ANSI B16.5 Weld Neck Flange	ANSI B16.5 Companion Flange
ANSI B16.5 Blind Flange	ANSI B16.5 Studding Outlets Flange
ANSI B16.5 Threaded Flange	ANSI B16.5 Lap Joint Flange
ANSI B16.5 Long Weld Flange

ANSI B16.5 Flange Applications

ANSI B16.5 Flange used in Heating
ANSI B16.5 Flange used in Plumbing
ANSI B16.5 Flange used in Chemical Industry
ANSI B16.5 Flange used in Water Supply Systems
ANSI B16.5 Flange used in Power Plant
ANSI B16.5 Flange used in General Purpose Applications
ANSI B16.5 Flange used in Oil and Gas Pipeline
ANSI B16.5 Flange used in Paper & Pulp Industry

ANSI B16.5 Flange Manufacturer in India

Nitech Stainless Inc has created a name in the Indian market as the leading manufacturer and supplier of ANSI B16.5 Flange in India. Nitech Stainless Inc has its manufacturing plants in different cities of India. Our steel flanges contain prime quality materials. factory-made from quality steel meeting ASTM and/or AISI standards as a result of higher the standard, higher is that the toughness of the ASTM | ASME | ANSI flanges.

ANSI Flanges Class 150, ANSI Flanges Class 300, ANSI Flanges Class 400, ANSI Flanges Class 600, ANSI Flanges Class 900, ANSI Flanges Class 1500, ANSI Flanges Class 2500,

IDENTIFY AND REPAIR FLANGE FACE CORROSION

The problem of Stainless Steel flange face corrosion

Piping systems in petrochemical refineries & oil & gas installations rely on hundreds of bolted joints which are exposed to corrosive conditions. To make sure safe operation at these plants it is vital to carry out regular inspection to assure joint integrity is maintained. Until recently, the usual procedure to do this was to physically disassemble each flange joint to check on its condition. Using this method was costly as it required shutdown & in many cases is entirely unnecessary. Before we look at the alternatives lets first take a look at the different types of flange corrosion.

Crevice & flange face corrosion

Crevice corrosion is the ‘bugbear’ of the oil & gas industry & is caused by a build-up of concentrated corrosive substances in the small confined area between two adjoining Stainless steel 304 flanges. Because of this concentration the rate of corrosion is much faster than elsewhere.

In addition to crevice corrosion, flange face corrosion is also broadly recognized as an integrity issue, due to the potential leak path created by the break in line. This can be in the form of small pits, often appearing in clusters on the flange’s sealing face. More information on types of corrosion is available in one of our previous blogs here.

Flange face inspection

As mentioned above, to disassemble a flange joint requires considerable cost in terms of both man hours & shutdown time, but technology now exists to enable non-invasive checks to be carried out while the pipe joint is still in service.

This uses ultrasound technology, but with multi-element probes to modify beam properties such as angle, standoff distance & focal properties. Phased array inspection is now growing in popularity thanks to its flexibility & the compact size of the units now commercially available.

When inspecting the raised flange face area, encoded magnetic scanners direct sound from the OD of the flange between the bolt holes. The ultrasound angles can be adjusted to fit the specific flange geometry & the multiple ultrasound angles used to optimize data displays of corrosion and/or erosion. The image above left shows a ss 304 flange in good condition with a normal reflective corner pattern. On the right the pattern is more haphazard & does not show a corner reflective pattern

How can corroded flanges be repaired?

When a flange face is damaged it is no longer sealable by a gasket & should be either replaced or repaired.

In general, there are four different types of repair to consider

Removing the corroded flange & welding a new one
On-site machining of the sealing face or ring groove within the flange tolerance
Add material (Weld buttering runs) & site machining of the sealing face or ring groove
Use of polymer composite repair materials to rebuild the flange face

What portable on-site machines are available to help?

Flange Face Repair

To machine the flange face sealing surface, a flange facing machine is the ideal product to get the job done quickly & accurately. Mirage Machines manufacture a wide range of machine options, including models that can be mounted internally or externally (and in some cases both). Smaller machines can be used for facing diameters as small as 2” with the largest being capable of facing up to 120 diameter.

Flange Removal

When repair of the flange is not possible, the remaining option is to change the flange entirely. This can be done using a split frame/clamshell pipe cutter. As the name suggests, the machine comprises of two sections which are fixed together & clamped around the pipe diameter.

Bolt Removal

This flange bolt cutter (or bolt slitting saw), is designed for removing seized stainless steel 304 flange bolts & offers a spark free cutting solution. It works by is cutting each bolt through the gap between the two adjoined flanges & can be used in either a conventional or upside-down orientation.